net: deduplicate sendfile files

The sendfile implementation for platforms supporting it is now in
net/sendfile.go, rather than being duplicated in separate files for
each platform.

The only difference between the implementations was the poll.SendFile
parameters, which have been harmonized, and also linux strictly
asserting for os.File, which now have been relaxed to allow any
type implementing syscall.Conn.

Change-Id: Ia1a2d5ee7380710a36fc555dbf681f7e996ea2ec
Reviewed-on: https://go-review.googlesource.com/c/go/+/664075
Reviewed-by: Damien Neil <dneil@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Auto-Submit: Quim Muntal <quimmuntal@gmail.com>

diff --git a/src/internal/poll/sendfile.go b/src/internal/poll/sendfile.go
index 41b0481c1aa38a9a695907a68d26ce73eceff80c..696d93353ebea2a1bd8b51fc0d35a099b3b7a760 100644 (file)
--- a/src/internal/poll/sendfile.go
+++ b/src/internal/poll/sendfile.go
@@ -4,4 +4,4 @@
 
 package poll
 
-var TestHookDidSendFile = func(dstFD *FD, src int, written int64, err error, handled bool) {}
+var TestHookDidSendFile = func(dstFD *FD, src uintptr, written int64, err error, handled bool) {}

diff --git a/src/internal/poll/sendfile_unix.go b/src/internal/poll/sendfile_unix.go
index 1105e0569110fb68afbd0aecb55c989a6ee5748e..4b7e9fea9e8dc98eb54e3055de8bf9910f4f75b2 100644 (file)
--- a/src/internal/poll/sendfile_unix.go
+++ b/src/internal/poll/sendfile_unix.go
@@ -27,29 +27,29 @@ import (
 // If handled is false, sendfile was unable to perform the copy,
 // has not modified the source or destination,
 // and the caller should perform the copy using a fallback implementation.
-func SendFile(dstFD *FD, src int, size int64) (n int64, err error, handled bool) {
+func SendFile(dstFD *FD, src uintptr, size int64) (n int64, err error, handled bool) {
        if goos := runtime.GOOS; goos == "linux" || goos == "android" {
                // Linux's sendfile doesn't require any setup:
                // It sends from the current position of the source file and
                // updates the position of the source after sending.
-               return sendFile(dstFD, src, nil, size)
+               return sendFile(dstFD, int(src), nil, size)
        }
 
        // Non-Linux sendfile implementations don't use the current position of the source file,
        // so we need to look up the position, pass it explicitly, and adjust it after
        // sendfile returns.
        start, err := ignoringEINTR2(func() (int64, error) {
-               return syscall.Seek(src, 0, io.SeekCurrent)
+               return syscall.Seek(int(src), 0, io.SeekCurrent)
        })
        if err != nil {
                return 0, err, false
        }
 
        pos := start
-       n, err, handled = sendFile(dstFD, src, &pos, size)
+       n, err, handled = sendFile(dstFD, int(src), &pos, size)
        if n > 0 {
                ignoringEINTR2(func() (int64, error) {
-                       return syscall.Seek(src, start+n, io.SeekStart)
+                       return syscall.Seek(int(src), start+n, io.SeekStart)
                })
        }
        return n, err, handled
@@ -58,7 +58,7 @@ func SendFile(dstFD *FD, src int, size int64) (n int64, err error, handled bool)
 // sendFile wraps the sendfile system call.
 func sendFile(dstFD *FD, src int, offset *int64, size int64) (written int64, err error, handled bool) {
        defer func() {
-               TestHookDidSendFile(dstFD, src, written, err, handled)
+               TestHookDidSendFile(dstFD, uintptr(src), written, err, handled)
        }()
        if err := dstFD.writeLock(); err != nil {
                return 0, err, false

diff --git a/src/internal/poll/sendfile_windows.go b/src/internal/poll/sendfile_windows.go
index f6d807d5d0a73bef4c012c6ce78b440e34a23588..d72bcd587102a828124550677127d5ad093fac55 100644 (file)
--- a/src/internal/poll/sendfile_windows.go
+++ b/src/internal/poll/sendfile_windows.go
@@ -10,7 +10,7 @@ import (
 )
 
 // SendFile wraps the TransmitFile call.
-func SendFile(fd *FD, src syscall.Handle, size int64) (written int64, err error, handled bool) {
+func SendFile(fd *FD, src uintptr, size int64) (written int64, err error, handled bool) {
        defer func() {
                TestHookDidSendFile(fd, 0, written, err, written > 0)
        }()
@@ -18,7 +18,8 @@ func SendFile(fd *FD, src syscall.Handle, size int64) (written int64, err error,
                // TransmitFile does not work with pipes
                return 0, syscall.ESPIPE, false
        }
-       if ft, _ := syscall.GetFileType(src); ft == syscall.FILE_TYPE_PIPE {
+       hsrc := syscall.Handle(src)
+       if ft, _ := syscall.GetFileType(hsrc); ft == syscall.FILE_TYPE_PIPE {
                return 0, syscall.ESPIPE, false
        }
 
@@ -29,11 +30,11 @@ func SendFile(fd *FD, src syscall.Handle, size int64) (written int64, err error,
 
        // Get the file size so we don't read past the end of the file.
        var fi syscall.ByHandleFileInformation
-       if err := syscall.GetFileInformationByHandle(src, &fi); err != nil {
+       if err := syscall.GetFileInformationByHandle(hsrc, &fi); err != nil {
                return 0, err, false
        }
        fileSize := int64(fi.FileSizeHigh)<<32 + int64(fi.FileSizeLow)
-       startpos, err := syscall.Seek(src, 0, io.SeekCurrent)
+       startpos, err := syscall.Seek(hsrc, 0, io.SeekCurrent)
        if err != nil {
                return 0, err, false
        }
@@ -49,7 +50,7 @@ func SendFile(fd *FD, src syscall.Handle, size int64) (written int64, err error,
                        // Some versions of Windows (Windows 10 1803) do not set
                        // file position after TransmitFile completes.
                        // So just use Seek to set file position.
-                       _, serr := syscall.Seek(src, startpos+written, io.SeekStart)
+                       _, serr := syscall.Seek(hsrc, startpos+written, io.SeekStart)
                        if err != nil {
                                err = serr
                        }
@@ -62,7 +63,7 @@ func SendFile(fd *FD, src syscall.Handle, size int64) (written int64, err error,
        const maxChunkSizePerCall = int64(0x7fffffff - 1)
 
        o := &fd.wop
-       o.handle = src
+       o.handle = hsrc
        for size > 0 {
                chunkSize := maxChunkSizePerCall
                if chunkSize > size {

diff --git a/src/net/sendfile_unix_alt.go b/src/net/sendfile.go
similarity index 89%
rename from src/net/sendfile_unix_alt.go
rename to src/net/sendfile.go
index db788753f1e7a8368b1de933b613152788519d6f..0a41241561bada566420bc53eb480a09b4e2b04a 100644 (file)
--- a/src/net/sendfile_unix_alt.go
+++ b/src/net/sendfile.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build (darwin && !ios) || dragonfly || freebsd || solaris
+//go:build linux || (darwin && !ios) || dragonfly || freebsd || solaris || windows
 
 package net
 
@@ -44,7 +44,7 @@ func sendFile(c *netFD, r io.Reader) (written int64, err error, handled bool) {
 
        var werr error
        err = sc.Read(func(fd uintptr) bool {
-               written, werr, handled = poll.SendFile(&c.pfd, int(fd), remain)
+               written, werr, handled = poll.SendFile(&c.pfd, fd, remain)
                return true
        })
        if err == nil {

diff --git a/src/net/sendfile_linux.go b/src/net/sendfile_linux.go
deleted file mode 100644 (file)
index 75af617..0000000
--- a/src/net/sendfile_linux.go
+++ /dev/null
@@ -1,55 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package net
-
-import (
-       "internal/poll"
-       "io"
-       "os"
-)
-
-const supportsSendfile = true
-
-// sendFile copies the contents of r to c using the sendfile
-// system call to minimize copies.
-//
-// if handled == true, sendFile returns the number (potentially zero) of bytes
-// copied and any non-EOF error.
-//
-// if handled == false, sendFile performed no work.
-func sendFile(c *netFD, r io.Reader) (written int64, err error, handled bool) {
-       var remain int64 = 0 // 0 indicates sending until EOF
-
-       lr, ok := r.(*io.LimitedReader)
-       if ok {
-               remain, r = lr.N, lr.R
-               if remain <= 0 {
-                       return 0, nil, true
-               }
-       }
-       f, ok := r.(*os.File)
-       if !ok {
-               return 0, nil, false
-       }
-
-       sc, err := f.SyscallConn()
-       if err != nil {
-               return 0, nil, false
-       }
-
-       var werr error
-       err = sc.Read(func(fd uintptr) bool {
-               written, werr, handled = poll.SendFile(&c.pfd, int(fd), remain)
-               return true
-       })
-       if err == nil {
-               err = werr
-       }
-
-       if lr != nil {
-               lr.N = remain - written
-       }
-       return written, wrapSyscallError("sendfile", err), handled
-}

diff --git a/src/net/sendfile_test.go b/src/net/sendfile_test.go
index 2b23f86ff0b12651a32285d7d2118bcd6af076a0..b5039ff1d18774730216f90e445019d8ddbae3a3 100644 (file)
--- a/src/net/sendfile_test.go
+++ b/src/net/sendfile_test.go
@@ -49,7 +49,7 @@ func expectSendfile(t *testing.T, wantConn Conn, f func()) {
                gotFD      *poll.FD
                gotErr     error
        )
-       poll.TestHookDidSendFile = func(dstFD *poll.FD, src int, written int64, err error, handled bool) {
+       poll.TestHookDidSendFile = func(dstFD *poll.FD, src uintptr, written int64, err error, handled bool) {
                if called {
                        t.Error("internal/poll.SendFile called multiple times, want one call")
                }

diff --git a/src/net/sendfile_windows.go b/src/net/sendfile_windows.go
deleted file mode 100644 (file)
index 731528f..0000000
--- a/src/net/sendfile_windows.go
+++ /dev/null
@@ -1,61 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package net
-
-import (
-       "internal/poll"
-       "io"
-       "syscall"
-)
-
-const supportsSendfile = true
-
-// TODO: deduplicate this file with sendfile_linux.go and sendfile_unix_alt.go.
-
-// sendFile copies the contents of r to c using the sendfile
-// system call to minimize copies.
-//
-// if handled == true, sendFile returns the number (potentially zero) of bytes
-// copied and any non-EOF error.
-//
-// if handled == false, sendFile performed no work.
-func sendFile(c *netFD, r io.Reader) (written int64, err error, handled bool) {
-       var remain int64 = 0 // by default, copy until EOF.
-
-       lr, ok := r.(*io.LimitedReader)
-       if ok {
-               remain, r = lr.N, lr.R
-               if remain <= 0 {
-                       return 0, nil, true
-               }
-       }
-
-       // r might be an *os.File or an os.fileWithoutWriteTo.
-       // Type assert to an interface rather than *os.File directly to handle the latter case.
-       f, ok := r.(syscall.Conn)
-       if !ok {
-               return 0, nil, false
-       }
-
-       sc, err := f.SyscallConn()
-       if err != nil {
-               return 0, nil, false
-       }
-
-       var werr error
-       err = sc.Read(func(fd uintptr) bool {
-               written, werr, handled = poll.SendFile(&c.pfd, syscall.Handle(fd), remain)
-               return true
-       })
-       if err == nil {
-               err = werr
-       }
-
-       if lr != nil {
-               lr.N = remain - written
-       }
-
-       return written, wrapSyscallError("sendfile", err), handled
-}

diff --git a/src/os/readfrom_solaris_test.go b/src/os/readfrom_solaris_test.go
index b11fbef0ff1daf69b38cf6eeda028903fcc29e18..b460f4c113e9f61ff090fec66ef9ed767763d4e5 100644 (file)
--- a/src/os/readfrom_solaris_test.go
+++ b/src/os/readfrom_solaris_test.go
@@ -48,10 +48,10 @@ func hookSendFileTB(tb testing.TB) *copyFileHook {
        tb.Cleanup(func() {
                poll.TestHookDidSendFile = orig
        })
-       poll.TestHookDidSendFile = func(dstFD *poll.FD, src int, written int64, err error, handled bool) {
+       poll.TestHookDidSendFile = func(dstFD *poll.FD, src uintptr, written int64, err error, handled bool) {
                hook.called = true
                hook.dstfd = dstFD.Sysfd
-               hook.srcfd = src
+               hook.srcfd = int(src)
                hook.written = written
                hook.err = err
                hook.handled = handled

diff --git a/src/os/writeto_linux_test.go b/src/os/writeto_linux_test.go
index 59caecd0da411fb2240f3722d04997b102f1274e..7d11bda74f7ad0a0f156358955e341bc2856adff 100644 (file)
--- a/src/os/writeto_linux_test.go
+++ b/src/os/writeto_linux_test.go
@@ -111,10 +111,10 @@ func hookSendFile(t *testing.T) *sendFileHook {
        t.Cleanup(func() {
                poll.TestHookDidSendFile = orig
        })
-       poll.TestHookDidSendFile = func(dstFD *poll.FD, src int, written int64, err error, handled bool) {
+       poll.TestHookDidSendFile = func(dstFD *poll.FD, src uintptr, written int64, err error, handled bool) {
                h.called = true
                h.dstfd = dstFD.Sysfd
-               h.srcfd = src
+               h.srcfd = int(src)
                h.written = written
                h.err = err
                h.handled = handled

diff --git a/src/os/zero_copy_linux.go b/src/os/zero_copy_linux.go
index 9d666a3c7911177658f9c0a7f6f23114a84abc4c..af30a68168af177181e6b5a4e50f1c9e91216ff5 100644 (file)
--- a/src/os/zero_copy_linux.go
+++ b/src/os/zero_copy_linux.go
@@ -28,7 +28,7 @@ func (f *File) writeTo(w io.Writer) (written int64, handled bool, err error) {
        }
 
        rerr := sc.Read(func(fd uintptr) (done bool) {
-               written, err, handled = poll.SendFile(pfd, int(fd), 0)
+               written, err, handled = poll.SendFile(pfd, fd, 0)
                return true
        })
 

diff --git a/src/os/zero_copy_solaris.go b/src/os/zero_copy_solaris.go
index 94a8de6062cfdcb37e2784800a35a8d30908e871..6000700fce76a5ba8777f1b83742985d67e7a94f 100644 (file)
--- a/src/os/zero_copy_solaris.go
+++ b/src/os/zero_copy_solaris.go
@@ -78,7 +78,7 @@ func (f *File) readFrom(r io.Reader) (written int64, handled bool, err error) {
        // https://docs.oracle.com/cd/E88353_01/html/E37843/sendfile-3c.html and
        // https://illumos.org/man/3EXT/sendfile for more details.
        rerr := sc.Read(func(fd uintptr) bool {
-               written, err, handled = poll.SendFile(&f.pfd, int(fd), remain)
+               written, err, handled = poll.SendFile(&f.pfd, fd, remain)
                return true
        })
        if lr != nil {